The present invention relates to fire-extinguishing devices for chimneys, particularly those that are to be incorporated in existing chimneys not originally built with fire-extinguishing equipment.
A major source of house fires is the combustion of flammable materials that have collected in chimneys. Although chimney fires have always occurred, the risk of such fires tended to decrease with the trend away from coal and wood to oil and natural gas. Accordingly, concern with cleaning chimneys has declined over the years. In very recent times, though, renewed use of, for instance, wood stoves and fire places has increased the buildup of flammable products in chimneys, sometimes without a corresponding increase in concern for cleaning the chimneys. It would thus be desirable that chimneys built during times when concern about chimney fires was rather low now be adapted to reduce the possibility of damage from such fires.
A number of chimney constructions exist in the prior art that provide for extinguishing fires that have started in the chimneys. An early example is illustrated in Shafer U.S. Pat. No. 883,149, and subsequent examples are illustrated in Albini U.S. Pat. No. 1,485,754, Dube U.S. Pat. No. 2,011,803, Theissing U.S. Pat. No. 2,024,316, Soucy U.S. Pat. No. 2,297,808, and Piagneri U.S. Pat. No. 2,351,365. Despite the number and variety of such constructions, it is thought that most are not particularly applicable to protecting existing chimneys. Some, such as Shafer and Albini, would clearly affect the draft in the chimney. Others, such as Soucy and Piagneri, require that electrical systems be wired into them. Dube exemplifies a type that would require significant custom construction work on the chimney, and others, such as Theissing, would be applicable to outdoor systems in only the most temperate of climates.
It is accordingly the object of the present invention to enable the user to readily fit an existing chimney with fire-extinguishing apparatus. It is another object that this result be achieved while keeping the amount of work expended in retrofitting and custom adaptation to a minimum. A further object is to avoid significantly affecting the draw through the chimney.